1. Field of the Invention
This invention relates generally to medical devices and anaesthesiology products, and particularly to an improved system for the secure inter-connection of tracheal tubes.
2. Background of the Technology
Endotracheal tubes are used regularly in hospitals around the world as an essential gas conduit when patients undergo anesthesia. The use of these devices has become widely accepted throughout the medical community and their design has become very standardized over the past twenty years with little change or improvement.
The distal end of the tracheal tube, that which projects outward from the patient, is commonly referred to as the machine end of the endotracheal tube. The machine end terminates in a connector for attachment to a breathing circuit or system. These endotracheal tube connectors have also become very standardized, and incorporate male-to-female conical tapers, that are intended to releasably but securely lock together relying on the friction fit of the tapered male-to-female connectors. While this friction fit connector allows ease of connection and disconnection it also permits the inadvertent disconnection of the breathing system from the tracheotomy tube. This inadvertent disconnection of the endotracheal tube from the breathing system during a surgical procedure is a well-recognized hazard that prior to the present invention was not well addressed in the medical community.
While attempts have been made to address the hazard of inadvertent disconnection of the endotracheal tube, the results have been largely unsuccessful. In addressing this issue, the medical profession refers to the hazard of inadvertent disconnection of the endotracheal tube in general terms in the ASTM standard F1590-95. In this publication, which is fully incorporated herein by reference, allowance is made for the addition of a mechanism to make a more secure attachment between the conical fittings, if so desired, suggesting a remedy in the form of retaining or locking devices such as hooks, lugs or studs. No specific design or guidance to arrive at a design is provided. An additional ASTM standard, F1243-89, which is fully incorporated herein by reference, makes reference to lugs, knobs or other projections that can be used to attach elastic bands to the connectors to resist accidental separation. For want of a more reliable means to releasably secure the tapered male-to-female connectors for endotracheal tubes, many hospitals have simply relied on this make-shift remedy of wrapping elastic bands around the connection.
More recently a new design for an endotracheal connector has been suggested by Sloan, U.S. Pat. No. 6,484,724. This device uses two concentric tapers to lock the endotracheal tube to the breathing system. The device of Sloan requires an entirely new design for the machine end of the endotracheal tube and therefore is incapable of being retrofitted to the existing worldwide inventory of endotracheal tubes and the endotracheal tubes that are currently in production. Further, the design of two concentric tapers provided by the Sloan device does nothing to remedy the fact that security of the connection is still solely reliant on a friction fit a male-to-female type connector. For this reason, an urgent need still exist in the medical art for a releasable means to ensure the security of currently used male-to-female connectors of the machine end of an endotracheal tube to a breathing system.